Diiodomethane → Biphenyl

Participants

Reaction Steps

To a cooled (0° C.) CH2Cl2 (22 mL) was added diethylzinc (1M in hexanes, 60.5 mL, 60.5 mmol) under nitrogen followed by the dropwise addition of trifluoroacetic acid (5.1 mL, 66.2 mmol) in 10 mL CH2Cl2 over 15 min. The reaction was stirred for 15 min, and then diiodomethane (5.4 mL, 66.9 mmol) in 10 mL CH2Cl2 was added dropwise to the reaction. The reaction was continued to stir at 0° C. for 1 hr, and then (E)-1,2-diphenylethene (2 g, 11.10 mmol) in 10 mL CH2Cl2 was added. The mixture was removed from the cold bath and stirred at ˜25° C. under nitrogen for 20 h. The reaction was quenched with 0.1N HCl (50 mL), the layers were separated, and the aqueous layer was extracted with hexanes (2×100 mL). The combined organic phase was washed with saturated NaHCO3 (aq) (50 mL) and brine (50 mL), dried over MgSO4, filtered, and concentrated in vacuo. The residue was submitted to a silica gel flash chromatography (hexanes) to afford biphenyl M9.3a as a colorless oil (1.6 g). 1H NMR (400 MHz, CDCl3) δ ppm 7.34-7.31 (m, 4H), 7.24-7.17 (m, 6H), 2.22-2.18 (m, 2H), 1.51-1.47 (m, 2H).

Provenance & Evidence